Tape loop control



1964 J. T. POTTER ETAL 3,156,423

TAPE LOOP CONTROL Filed May 18, 1962 Peer.

DEA/E I I .30 37 34 l An'uum (m/mu INV NToRs div/N T507752 ANDQEWG/LBOATTORNEY United States Patent 3,156,423 TAPE L001 CONTROL John T.Potter, Locust Valley, and Andrew Gabor, Port Washington, N.Y.,assignors to Potter Instrument Company, Inc., Plainview, N.Y., acorporation of New York Filed MaylS, 1962, Ser. No. 195,709 12 Claims.(Cl. 242-5512) This invention, generally, relates to tape handlerapparatus and, more particularly, to a tape loop control for suchapparatus.

When it is desired to move tape at rapid rates for processinginformation, it is usually desirable to maintain intermediate tapestorage facilities, such as in the form of one or more loops of tape, toprovide increased flexibility of operation. The vacuum tank is uniquelyfitted to provide the desired tape loop control because of its lowinertia characteristics, but it still is desirable to develop andmaintain accurate control over the tension in the loop of tape stored inthe vacuum tank.

Accordingly, it is an object of this invention to provide a new andimproved control for a tape loop in a vacuum tank.

Another object of the present invention is to provide a tape loopcontrol adapted to function with a vacuum receptacle.

Briefly, the invention contemplates the provision of a vacuum tankhaving a tape loop-receiving opening and at least a portion of one sideof the tank being movable. A linkage is connected between the movableside portion and a reference point. A suitable control means isconnected with the linkage at a point intermediate the vacuum tank andthe reference point and responsive to move- "ment in the linkage toinfluence the operation of a predetermined external component, such as avacuum source or a reel drive mechanism or both.

The above and other objects and advantages of the invention will becomemore apparent from the following detailed description of a preferredform thereof taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a diagrammatic view illustrating an arrangement in accordancewith the principles of the invention;

FIG. 2 is a diagrammatic view illustrating different lengths of linkagesin accordance with the invention;

FIG. 3 is a fragmentary view of a valve controllable by the linkages ofFIG. 1; and

FIG. 4 shows an electrical component variable in accordance withmovement of a linkage such as shown in FIG. 1.

Referring nowto FIG. 1 of the drawings, a'tape storage means is providedin this instance by a reel supported rotatably as is well known, and atleast two vacuum storage tanks indicated generally by the numerals Y11and 12 are positioned appropriately relative to the reel 10 to receive aloop of tape 13 in each tank. A roller 14 is positioned between the twotanks 11 and 12, if desired, to guide the tape 13 as it leaves the firsttank 11 on its way into the second tank 12.

The vacuum tank 11 is'formed of three vertical sides, sides 15 and 16being visible in FIG. 1, and these sides are fixed in position relativeto each other. A bottom surface 17 closes the lower end of the tank 11and provides a suitable connection 18 for receiving a conduit 19 toconnect a vacuum source to the tank 11. Of course, the connection 18located on the bottom surface 17 is merely illustrative, the inventionbeing applicable also to structures which locate this connectionotherwise than as shown.

While the fourth side 20 of the tank 11 is shown pivotable about an axis21 adjacent the bottom 17 of the tank 11, the axis 21 may be at anydesired location to provide a movable portion at the upper end thereofIt is required only that the upper end 22 is movable toward and awayfrom the side 15.

The second vacuum tank 12 is constructed in a similar manner to thatjust described above in connection with the first vacuum tank 11, and isprovided with a movable side 23 pivotable about an axis 24 also similarto the vacuum tank 11. A conduit 25 provides means to connect a vacuumsource to the tank 12.

Two linkages 26 and 27 are pinned at points 28 and 29, respectively,adjacent the upper ends'of the movable sides 20 and 23. The oppositeends of these two linkages 26 and 27 are pinned together as indicatedgenerally by the numeral 30, and the arrows at the point 30 indicate theprincipal axes of movement of this connection point Therefore, the twolevers 26 and 27 translate any movement of the sides 20 and 23 intocomponents of movement indicated by the arrows at the point 30. In otherwords, if the point 30 moves upwardly and to the right at some angle,say 45, this movement will be translated into a vertical component and ahorizontal component in the direction of the arrows.

Movement of the side 20 and 23 is developed by the vacuum drawn on theinside of each tank as related to the position of the tape loop withineach tank. For example, as a loop gets shorter or closer to the top of atank, a greater portion of the inside of the tank is at reduced pressurecausing the movable side to be drawn inwardly. On the other hand, as atape loop sinks lower in a tank, the volume of the tank above. the loopbeing at atmospheric pressure causes the movable side to be deflectedoutwardly under the action of a suitable bias, such as a spring in thehinges or by springs S and S, if desired.

The movement of the point 30 is useful in controlling selectedcomponents of a tape handler apparatus. While any desired component maybe controlled, the degree of vacuum and the reel drive servo areselected for illustrative purposes.

The vacuum is controlled as illustrated in FIG. 3 of the drawings whichshows a valve 31 having an inner valve head 32 pivotable about an axis33 as indicated by the double-headed arrow 32' (FIG. 3) under the actionof a link 34 which is movable in the direction of the arrow 35 (FIG. 1).

To illustrate the operation of this valve 31, assume that the loop oftape becomes short in the tank 11 and the vacuum is pulling the side 20inwardly. This movement of the point 36 has an upward component which istranslated through the linkage 34 to the inner valve head 32 in adirection tending to close the conduit 19 thereby reducing the amount ofvacuum being pulled by a vacuum pump 36.

The operation of the valve 31 is similar for the tank 12 and attempts tomaintain a balance in vacuum between the two tanks.

As mentioned previously, any movement in the two linkages 2s and 27 istranslated through horizontal and vertical movements of the point 30,and the linkage 34, therefore, must be adapted to be nonresponsive tohorizontal movement of the point 30, for the particular controlillustrated. This is accomplished by forming the linkage 34 with atubular portion 37, and a rod 38 is attached to slide within the tubularportion 37 in a horizontal manner. Therefore, any horizontal movement ofthe point so does not affect the position of the linkage 34. Of course,the vertical movement just described may be used to control the vacuumsource, in a different manner such as by the means shown in FIG. 4 ofthe drawings. The vertical movement of the point 30 is shown attached tomove a movable contact 38 of a potentiometer 39 to vary a vacuum controlcircuit 40. The movable contact 38 has a tubular portion 41 to receive apin 42 so that horizontal motion of the point does not affect theposition of the contact 38.

Referring again to FIG. 1 now, horizontal motion of the point 30 may beused to move a rod 43 in the direction of the arrows 44 for adjusting apotentiometer 45 to control a reel drive circuit 46. The rod 43 isslidaole in a fixed reference member 47, in the arrangement shown in thedrawings.

So that vertical movement of the point 30 does not adversely affect theslidable rod 43, a universal joint 48, or any other flexible connection,couples the point 30 with the slidable rod 43.

Referring now to FIG. 2 of the drawings, the two vacuum tanks 11 and 12are illustrated diagrammatically with the movable sides 20 and 23indicated as pivotable at the points 21 and 24. In the solid lines,linkages St) and 51 are relatively short and are pinned together at apoint 52. With this length of linkages, the point 52 has a smallerdistance of movement for a given deflection of either side 20 or 23, butwith a greater force is developed in the movement of the point 52.

Comparing the length of the linkages and 51 with a length indicated bythe dotted lines 53 and 54, such length of linkages may be pinned at apoint 55 to achieve a larger degree of movement of the point 55.However, this larger movement of the point 55 is at a lower force thanis developed at the point 52.

Therefore, the length of the connecting linkages may be selected by thedesigner in accordance with the operating characteristics desired andthe component to be operated.

Other modifications will occur to one skilled in the art to which theinvention pertains, and it is understood that the scope of the presentinvention is defined by the claims appended hereto.

What is claimed is:

1. In tape handler apparatus, means to control tension in a tape,comprising:

first tape storage means adapted to provide a supply of tape forprocessing information in accordance with a predetermined schedule,

at least one temporary tape storage means including means to providesufficient tension on a tape to absorb slack and including a movableportion adapted to be continuously urged to be moved by said ten sionmeans throughout a range of positions in response to and proportional tothe position of the tape in the temponary tape storage means,

first means connected at a first point to the movable portion,

second means connected at a second different point,

and

third means interconnecting said first and second means whereby movementof the movable portion produces a movement of the third means in amanner different in magnitude but proportional to the movement of themovable portion to control tension in the tape.

2. In tape handler apparatus as set forth in claim 1 wherein said firsttape storage means is in the form of a reel supported rotatably to payout a supply of tape.

3. In tape handler apparatus as set forth in claim 1 wherein said onetemporary tape storage means is in the form of a vacuum chamber,

4. In tape handler apparatus as set forth in claim 1 including a secondtemporary tape storage means adapted to provide tension on a tape andincluding a movable portion similar to the first-mentioned movableportion, and

said second, different point is on the movable portion of the secondtemporary tape storage means.

5. A tape loop control comprising a vacuum tank having a tapeloop-receiving opening and including means for providing a vacuumtherein, at least a portion of one side of said vacuum tank beingmovable, said movable portion being adapted to be continuously urged tobe moved by said vacuum throughout a range of positions in response toand proportional to the position of the tape in the vacuum tank,

linkage means connected at a point on said movable portion of saidvacuum tank side and a reference point, and

means connected with said linkage means at a point intermediate thevacuum tank and the reference point to influence the operation of apredetermined external component in a manner different from butproportional to movement of said one side to control tension in thetape.

6. A tape loop control as set forth in claim 5 wherein said connectionmeans is connected between said linkage means and a control for saidmeans providing said vacuum.

7. A tape loop control as set forth in claim 5 wherein said connectionmeans is connected betwen said linkage means and a control for a tapereel drive mechanism.

8. A tape loop control as set forth in claim 6 wherein said connectionmeans include means responsive only to a predetermined component ofmovement in said linkage means.

9. A tape loop control as set forth in claim 7 wherein said connectionmeans include means only to a predetermined component of movement insaid linkage means.

10. A tape loop control as set forth in claim 5 wherein said connectionmeans is connected between said linkage means and a control for saidmeans providing the vacuum and said control including means responsiveonly to a predetermined component of movement in said linkage means, andsaid connection means also being connected with a control for a tapereel drive mechanism and said last-mentioned control including meansresponsive only to a component of movement in said linkage meansdifferent from said predetermined component.

11. A tape loop control as set forth in claim 10 wherein said differentcomponent of movement in said linkage means is substantially degreesfrom said predetermined component.

12. A tape loop control as set forth in claim 5 includmg a second vacuumtank having a tape loop-receiving opening,

at least a portion of one side of said second vacuum tank being movable,and

said reference point to which said linkage means is connected being onsaid movable side portion of said second vacuum tank.

References (Iited in the file of this patent UNITED STATES PATENTSUNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent. No, 3,156,423 November 10, 1964 John T., Potter et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 4, line 18, for "at" read between Signed and sealed this 20th dayof April 1965.

(SEAL) Attest: i ERNEST W. SWIDER EDWARD J BRENNER ing OfficerCommissioner of Patents

1. IN TAPE HANDLER APPARATUS, MEANS TO CONTROL TENSION IN A TAPE,COMPRISING: FIRST TAPE STORAGE MEANS ADAPTED TO PROVIDE A SUPPLY OF TAPEFOR PROCESSING INFORMATION IN ACCORDANCE WITH A PREDETERMINED SCHEDULE,AT LEAST ONE TEMPORARY TAPE STORAGE MEANS INCLUDING MEANS TO PROVIDESUFFICIENT TENSION ON A TAPE TO ABSORB SLACK AND INCLUDING A MOVABLEPORTION ADAPTED TO BE CONTINUOUSLY URGED TO BE MOVED BY SAID TENSIONMEANS THROUGHOUT A RANGE OF POSITIONS IN RESPONSE TO AND PROPORTIONAL TOTHE POSITION OF THE TAPE IN THE TEMPORARY TAPE STORAGE MEANS, FIRSTMEANS CONNECTED AT A FIRST POINT TO THE MOVABLE PORTION, SECOND MEANSCONNECTED AT A SECOND DIFFERENT POINT, AND THIRD MEANS INTERCONNECTINGSAID FIRST AND SECOND MEANS WHEREBY MOVEMENT OF THE MOVABLE PORTIONPRODUCES A MOVEMENT OF THE THIRD MEANS IN A MANNER DIFFERENT INMAGNITUDE BUT PROPORTIONAL TO THE MOVEMENT OF THE MOVABLE PORTION TOCONTROL TENSION IN THE TAPE.